1. Field of the Invention
The present invention relates to a socket, and more particularly to a socket for burn-in tests.
2. Description of the Related Art
European Patent Application No. 1091628 discloses a socket including a base or main socket body 2, an operating cover member 3 movable mounted on the socket body 2, electrically conductive contact members 4, and a spring 5. The socket body 2 is provided with an IC package seating surface 2b for receiving the IC package 6. The IC package 6 has body 60 in the form of a thin rectangular polyhedron and a selected number of IC terminal leads 61 extending outwardly from opposing sides of the body in the lateral direction. Each contact member 4 has a generally U-shaped central portion comprising a first and a second mounting legs 40 and 41 and a number of leads 42 extending from the second mounting leg 41 beyond a bottom of the socket body 2 for connection to a printed circuit board. A first and a second contact parts 43 and 44 opposing to each other are provided on the first mounting leg 40. The first contact part 43 comprises a spring part 43a extending from an upper edge of the first mounting leg 40 and a bifurcated end forming a contact arm part 43b and a lever part 43c. Tip of the contact arm part 43b forms a first electrical contact 43e. The second contact part 44 comprises an arm 44a extending from an upper edge of the first mounting leg 40 and a second electrical contact 44b is formed on tip of the arm 44a and an engagement part 44c is formed on the middle area of arm 44a adapted for positioning and engaging the second contact part 44 relative the socket body 2.
Before the contact member 4 is mounted on the socket body 2, the second electrical contact 44b is so formed as to be somewhat separated from the first electrical contact 43e. When the operating cover 3 of the socket is pressed down, a cam surface 32 formed on the operating cover 3 engages the follower tip of the lever part 43c of the contact member 4 and if the operating cover 3 is further pressed down, the lever part 43c of the contact member 4 is cammed along the cam surface 32 of the operating cover 3. Along with this, the first electrical contact part 43e moves in a direction away from the second electrical contact 44b of the contact member 4. When there is no downward force on the operating cover 3, the operating cover 3 is pushed up by a spring forces of the spring 5 and the contact member 4. In conformity with this, each IC package terminal lead 61 is sandwiched by the first and second electrical contact 43e and 44b of a respective contact member 4 and the IC package terminal lead 61 are electrically connected.